Method and apparatus for making a non-gussetted bag with satchel bottom adapted to provide an open container with square corners



March 20, 1962 R. P. KESSLER 3,025,768

METHOD AND APPARATUS FOR MAKING A NON-GUSSETTED BAG WITH SATCHEL BOTTOM ADAPTED TO PROVIDE AN 7 OPEN CONTAINER WITH SQUARE CORNERS Filed March 16, 1956 2 Sheets-Sheet 1 INVENTOR Fair/1rd flrsslflr BY 67/15, //M x o ATTORNEYS March 1962 R. P. KESSLER 3,025,768

METHOD AND APPARATUS FOR MAKING A NON-GUSSETTED BAG WITH SATCHEL BOTTOM ADAPTED TO PROVIDE AN OPEN CONTAINER WITH SQUARE CORNERS Filed March 16, 1956 2 Sheets-Sheet 2 INVENTOR ATTORNEYS United States Patent METHOD AND APPARATUS FOR MAKING A NON-GUSSETTED BAG WITH SATCHEL BOT- TOM ADAPTED TO PROVIDE AN OPEN CON- TAINER WITH SQUARE CORNERS Richard P. Kessler, Canaioharie, N.Y., assignor to West Virginia Pulp and Paper Company, New York, N.Y., a corporation of Delaware Filed Mar. 16, 1956, Ser. No. 571,944 2 Claims. (Cl. 93-35) This invention relates to apparatus and method of making a non-gusset-ted paper bag with satchel bottom which when open presents a container with square corners and cross section in the general form of a rectangle.

When non-gussetted satchel bottom bags are made with ordinary machines the open bag is very much like an envelope which in cross section tapers down to a point at each side and as a result the open container does not have the desired square corners. In accordance with my invention I provide scoring apparatus adapted to sharply score the paper from which the non-gussetted bag is made and the scoring is carried out on thepaper when it is flat before being fed into the bag tube forming apparatus. The scoring apparatus of my invention position four substantially parallel score lines longitudinally along the length of the paper and the score lines are so positioned that each score line terminates in a corner of the bottom end closure of the open bag which then present a container with square corners and cross section in the general form of a rectangle.

My invention may be readily understood by reference to the accompanying drawings illustrating a single ply bag in which FIG. 1 is a diagrammatic top view of a bag forming machine which includes my scoring apparatus;

FIG. 2 is a front view of my scoring apparatus taken on line 2-2 of FIG. 1;

FIGS. 3 and 4 are an enlarged isometric view of the scoring apparatus of FIG. 2 opened up to show its construction;

FIGS. 5 through 8 illustrate the steps involved in forming an end closure for the bag tube;

FIG. 9 illustrates a modified form of scoring apparatus; and

FIG. 10 is a cross section taken on line 10-10 of FIG. 9.

Referring now to FIG. 1 of the drawings 10 is a roll of a ply of paper 12 from which the bag is made. The bag machine is not illustrated in detail as these machines are well known in the art and readily available on the open market. In such a machine the ply of paper 12 is fed through a series of suitable rolls 14 Where a line of adhesive is applied longitudinally along one side portion of the paper as at 16. The ply of paper then passes into the tube former 17 Where the paper is folded over on itself and side portions of the paper ply are overlapped and pasted together to form a flattened bag tube as at 18. The flattened bag tube has a crease line 19 along each side. As best shown in FIGS. 5 and 6 in the type of bag to which this invention relates there is a single crease line 19 on each side of the bag tube which divides the tube into two equal side wall panel sections. The crease line 18 constitutes the limit of the side fold of the bag when in flat unfolded condition and the paper in the side crease line is outfolded so that the apex of the fold of the crease line is on the exterior of the bag and not inside. Tube 18 is then fed into the bag bottomer 20 where the tube is severed into bag lengths 21 and then one end of the tube is folded and pasted closed in the usual way to form a satchel end closure 22. These steps of forming the bag 3,025,768 Patented Mar. 20, 1962 length of flattened tube and satchel bottom end closure in the tube are old and Well known in the art.

In accordance with my invention I provide scoring apparatus 24 which is positioned in the bag making machine in front of the tube former whereby scoring apparatus is operative to score the singly ply of paper before it is fed into the bag tube forming apparatus. As shown in the drawings my preferred form of scoring apparatus includes a bar 28 having four grooves 30 positioned therein each of which is preferably in the general form of a V. The V-shaped grooves preferably run from the top to the bottom of the bar and a shoe 32 carried by bar 34 is provided for each groove. The shoes 32 are adapted to fit into the V-shaped grooves so that the ply of paper 12 is sharply scored as it passes between the groove and shoe. In the preferred form of my invention shown in FIGS. 1 through 8 the scoring edge of each shoe is inclined upwardly away from the point at the bottom of the V of the groove so that the score line is gradually formed in the paper (see FIG. 2). This is important since the paper is gradually stretched as it is scored and as a resultscoring is accurately controlled, and the score lines are much more permanent than in the case where scoring is carried out without stretching the paper by leading it in as for example with wheels Where the score is made at a single point.

Referring to FIGS. 1 and 5 it will be seen that the four grooves 30 with cooperating shoes 32 are operative for forming four substantially parallel longitudinal score lines 36 in the paper ply 12. The space between each score line 36 and the position of the score lines in the ply is critical andthe score lines are so positioned that each one intersects a corner of the end closure 22 which is formed when side flaps 38 and end flaps 40 are infolded into-the bag tube to form end closure 22. As shown in FIGS. 5 through 8 satchel end closure 22 is formed in the usual way by positioning four longitudinal slits 42 in the paper adjacent the open mouth 44 of the length of bag tube so that opposite portions of the tube Wall may be folded inwardly to give side flaps 38 and overlapping end flaps 40 which cover the side flaps and are held in place by means of adhesive 46. As shown in FIG. 7, in the finished structure a portion of the end closure for the bag is folded down against the body of the bag and the end closure is held in a plane substantially parallel to the plane of the bag tube. As a result the opposite side walls of the bag tube are creased as at 48. The open bag tube is shown in FIG. 8 and as there shown it presents a container with square corners with cross section in the general form of a rectangle. Of course if desired the cross section of the bag may be in the form of a square (not shown).

Referring to FIG. 5 it Will be seen that the four score lines at the corners of the open container are so made in the fiat ply of paper that the score line is outfolded that is, the paper is scored from inside the tube out. Since the exact position of the score lines is critical shoes 32 are slidably mounted on bar 34 by means of a slot 50 and bolts 52 so that the position of the shoes on the bar relative to each other may be changed. Bar 34 is also slidably mounted in the bag forming machine by mean of slots 54 and 56 so that the position of the bar may be changed as desired. Bar 28 is also slidably mounted by means of slots 58 and 60 so that the position of the four V-shaped grooves may be changed relative to the position of the ply of paper in the machine, Since the position of the V-shaped grooves in the bar can not be changed separate bars are made up for each size bag to be manufactured in accordance with my invention.

In FIGS. 9 and 10 I illustrate a modified form of apparatus for positioning my score lines 36 in the bag tube. As there shown the score lines are made by means of male Wheels 62 which mate with female Wheels 64 in known manner to score the paper. The male and female wheels are each rotatively mounted on rods 66 and 68 respectively and the wheels are held in place by set screws 70 so that the position of the wheels on the rods may be changed relative to each other. Although point scoring of male and female wheels is not as satisfactory as the gradual scoring achieved with the V-shaped grooves, point scoring of the wheels does give a commercial product.

It will be understood that I intend to cover all changes and modifications of the preferred form of my invention herein chosen for the purpose of illustration which do not constitute departures from the spirit and scope of my invention.

What I claim is:

1. In a paper bag tubing machine of the type adapted to operate continuously and form a non-gussetted bag tube having a square bottom end closure therein and a single crease line along each side of the tube which constitutes the limit of the side of the flattened bag tube, the

improvement which comprises apparatus for positioning four spaced parallel score lines in the paper of the bag tube While in fiat unfolded condition which apparatus includes a stationary member having four indentations in the surface thereof, each of said indentations being in the general form of a V-shaped notch which is at least twice as long as it is wide and which is adapted to contact one side of the paper over substantially the entire surface of the area to be scored, a cooperating shoe which is at least twice as long as the V-shaped notch is wide held in stationary position in each of the said V-shaped notches, each of said shoes being adapted to provide a gradually decreasing space between the edge of the shoe and bottom of the V-shaped notch and each of said coopcrating shoes being held in position to press against the second side of the paper over substantially the entire surface of the area to be scored with gradually increasing force to form a sharp score line in the paper while the paper of the bag tube is fed in flat unfolded condition between the said generally V-shaped notches and coopcrating shoes, said V-shaped notches and cooperating shoes being held in position to provide four permanent score lines in the paper of the bag tube which extend from the open mouth of the tube down to a corner of the and closure to provide square corners in the wall of the opened tube that correspond to the square corners in the end closure of the bag.

2. The method of providing square corners in the wall of a non-gussetted paper bag tube of the type having a so-called square bottom end closure and a single crease line along each side of the tube which constitutes the limit of the side of the bag tube when flat comprising the steps of continuously feeding the paper for the bag tube in fiat unfolded condition into bag tubing apparatus, forming four spaced parallel score lines in the paper of the tube while it is being fed in flat unfolded condition through the bag tubing apparatus each of said score lines being formed by simultaneously pressing stationary members against both sides of the flat paper over substantially the entire surface of the area of the paper to be scored with steadily increasing force applied in the direction of travel of the paper to gradually stretch the paper and thereby provide a permanent score line therein, applying said force against both sides of the paper over a distance which is at least twice as long as the depth of the score line, positioning each of said score lines in the paper of the bag tube to extend from the open mouth of the tube down to one of the corners of the end closure thereof to provide square corners in the wall of the opened tube that correspond to the square corners in the end closure of the bag.

References Cited in the file of this patent UNITED STATES PATENTS 743,124 Wikander Nov. 3, 1903 1,421,817 Novick July 4, 1922 1,687,683 Mogel Oct. 16, 1928 1,926,421 Andreas Sept. 12, 1933 2,013,086 Baker Sept. 3, 1935 2,311,248 Poppe Feb, 16, 1943 2,420,212 Volksdorf May 6, 1947 2,432,053 Waters Dec. 2, 1947 FOREIGN PATENTS 147,088 Sweden Sept. 21, 1954 855,357 Germany Nov. 13, 1952 877,539 Germany May 26, 1953 

